An Introduction to N:P:K
During the growing season plants absorb important nutrients & minerals from the soil, these need to be replaced if your plot is to maintain a high level of productivity. Most general purpose fertilisers have an N:P:K rating which relates to the three main elements needed for healthy plant growth. The higher the rating the more of that element exists within the fertiliser.
Nitrogen ( N )
Supports the growth of vegetable parts of plants, leaves & stems. Leafy vegetable’s such as spinach, cabbage, lettuce, have a high nitrogen requirement. Lack of nitrogen causes poor, stunted growth with spindly stems with yellow & discoloured leaves. Nitrogen washes out of the soil so feeds need to be applied over the growing season.
Phosphorus ( P )
Stimulates seed germination & root development, increases stem strength & improves flower formation. Root vegetable’s need plenty of phosphorus to aid development. Lack of phosphorus causes poor, stunted growth, plants produce little or no flowers with a weak root system.
Potassium ( K )
Essential for flower & fruit development, also improves drought pest & disease resistance. Often referred to a “quality element” because of the importance to many of the features associated with quality, such as shape, size colour, & taste. Potatoes, fruit, & tomatoes need a high yield of potassium to crop well. Plants low in potassium are stunted in growth & provide lower yields. Excessive levels of potassium can lead to magnesium & calcium deficiencies. Minerals & also trace elements are important for good plant health, over time with each & every harvest, the soil is depleted of these vital ingredients & they also need replacing.
Blog & Research By Mark Burton (Allotment Secretary)
